The invention pertains to a method for adjusting the brake force distribution between a towing vehicle and a trailer as a function of the weight of the trailer as well as a device for carrying out said method.
It has been known for quite some time that the brake force between a towing vehicle and a trailer needs to be adjusted as a function of the load of the trailer so as to obtain an optimal braking effect and prevent the forces on the trailer coupling from becoming excessively high. In older systems, a valve on the trailer was actuated manually (this also applies to railroad cars) if the load was changed. However, more modern systems have automated this process by measuring the load of the trailer if said trailer is equipped with a pneumatic suspension and actuating a control unit for distributing the brake force as a function of said load measurement. In other systems, the coupling force between the towing vehicle and the trailer was measured on the trailer coupling by means of sensors that are sensitive to tension or pressure, with the brake force distribution being adjusted as a function of these measured values.
However, it was established that most sensors are unable to withstand the rough conditions that exist during the operation of a truck or a railroad, i.e., these sensors frequently fail. The utilization of sensors that are designed as electromechanical transducers is associated with substantial expenditures for the signal transmission which in most instances is accomplished by electric cables. If the signals are transmitted from the trailer to the towing vehicle or vice versa, said transmission requires additional plug connections or plug couplings that must be protected against water, the penetration of dirt, salt, etc., with high expenditures.